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Alex October 9, 2002 09:14

Fluid / Particle Interaction
Hi! I have a (hopefully trivial, at leat for someone out there) problem: I am trying to simulate the acceleration of abrasive particles (garnet) in a high velocity fluid stream. I have a pressure in- and outlet and a surface particle injection (fluid/particle interaction switched on). The problem is: After iteration, the particles have in every position exactly the same speed as the fluid, so that they appear not to have any inertia. What am I doing wrong? Thanks in advance, Alex

Vaibhav October 10, 2002 05:40

Re: Fluid / Particle Interaction
hi i think u should try the fluid inlet and a solid inlet(high density fluid in eulerian- eulerian grannular model ) instead of the surface particle injection. that may help u . beacuse in surface particle injection solid behave as inerts. so they acuire same velocity as that of fliud.

CFD Newbie October 10, 2002 10:49

Re: Fluid / Particle Interaction
Have you turn on gravity ( a must)?

What is the density of your particles?, if small, inertial effects are not present.

Is your particle tracking in unsteady state?

Have you tried particle-flow interaction?

All these factors have an impact on the behavior of your particle tracks. Try all of them.


CFD Newbie

zahir October 11, 2002 05:53

Re: Fluid / Particle Interaction
I am looking into moddeling a similar flow. I want to model diesel exhaust flow with very many different constiuants. is this possible in fluent. Any ideas. Thanks

Sreedhar October 21, 2002 12:21

Re: Fluid / Particle Interaction

Your particles will have have more or less the same velocity as the fluid if the particle size and/or density is very small (in this case fluid inertia dominates the particle inertia)and if the number of particles is not large enough to consider a 2-way/4-way coupling of the multiple phases.

Also, as you would have observed, (for a 1-way coupling) the particles will follow the fluid streamlines all along unless there is any solid obstruction in their path. Hope this helps.

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